The distribution of particulate material onto surfaces, such as salt or sand onto roadways and fertilizer onto fields, is commonly provided by use of a chassismounted particulate supply body and associated spreader device. One popular form of supply body is commonly referred to as a V-Box. V-Box bodies are open at the top to receive particulate material therein and have, as their name implies, straight, downwardly sloped sides, generally in the shape of a "V." These sloping sides function to direct the particulate material toward the lower center of the body.
The particulate material is loaded into the V-Box through the open top portion. The open top portion of the V-Box is commonly covered by at least one screen. The screen allows the material to flow into the V-Box, but prevents personnel from entering the V-Box. A V-Box will commonly have at least two screens, with each screen being pivotally mounted to the V-Box along its longitudinal centerline.
A conveyor, such as an auger, is also provided in the lower portion of the V-box. The auger extends from the front of the V-Box to at least the rear of the V-Box, and typically beyond the rear of the V-Box. The auger functions to move the material to the rear of the V-Box, and typically extends into a spreader device located at the rear of the V-Box to ensure movement of desired quantities of particulate material from the V-Box into the spreader device.
The spreader device, located at the rear of the V-Box, includes a hopper having an inlet that receives particulate material from the V-Box and an outlet to distribute the particulates. An auger is also located in the lower portion of the hopper to move the particulates within the spreader device, and a pivotable cover is provided on the upper portion of the hopper to prevent access to the interior of the hopper. The auger in the spreader body is typically the rearward extending portion of the same auger that is located in the supply body, but may also be a second, separate, auger. A spinner is often located under the outlet of the spreader to scatter the particulate material across the surface over which the spreader travels.
To perform maintenance or clean up, the spreader cover and V-Box screens are sometimes opened. This exposes personnel to the auger. Further, because power is available to the motor that drives the auger when the covers are opened, there exists a possibility that the auger would inadvertently be activated while the personnel were in contact with the auger.
A system is therefore required to reduce the possibility of inadvertent activation of the auger when the spreader cover or supply body screens are opened. Such systems must further be reliable in a corrosive environment, be relatively easy to use in harsh environmental conditions, and be relatively difficult to disable or circumvent.